Metastatic renal cell carcinoma has proven to be generally unresponsive to all agents evaluated to date including most alkylating agents, antimetabolites, and antibiotics. Progesterone derivatives or androgens give a low number of partial remissions and about a 20% subjective response rate. Many currently available chemotherapeutic agents have not yet been adequately evaluated including three agents for which there are preliminary data to suggest some responsiveness, i.e., CCNU, vinblastine and thio-TEPA. These three drugs were therefore tested in prospective randomized trial of therapeutic efficacy in patients with metastatic renal cell carcinoma. Patients whose tumors progressed on this study were then treated with bleomycin for which there were also some early data suggesting possible value in this disease. A partial response was seen in one of seven thio-TEPA treated patients, zero of nine CCNU treated patients and zero of ten vinblastine treated patients although two of the latter had an objective response. None of seven bleomycin treated patients had an objective response.